M87.277
BillableOsteonecrosis due to previous trauma, right toe(s)
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is M87.277 an HCC code?
Yes. M87.277 maps to Bone/Joint/Muscle Infections/Necrosis under the CMS-HCC V28 risk adjustment model (and Bone/Joint/Muscle Infections/Necrosis under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for M87.277
For M87.277 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed M87.277 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
M87.277 is the ICD-10-CM diagnosis code for osteonecrosis due to previous trauma, right toe(s). Death of bone tissue in the right toe(s) caused by a previous injury or trauma. M87.277 sits in the ICD-10-CM chapter for diseases of the musculoskeletal system and connective tissue (m00-m99), within the section covering other osteopathies (m86-m90).
Under the CMS-HCC V28 risk adjustment model, M87.277 maps to Bone/Joint/Muscle Infections/Necrosis (HCC 92) with a community, non-dual, aged base RAF weight of 0.209. Under the older V24 model, M87.277 mapped to the same category but with a base RAF weight of 0.482 — V28 recalibrated weights across the entire model. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Verify documentation specifies 'right toe(s)' and confirm whether one or multiple toes are affected. Because M87.277 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for M87.277 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify documentation specifies 'right toe(s)' and confirm whether one or multiple toes are affected
- •Use this code specifically for toe involvement rather than general foot osteonecrosis
Clinical Significance
Right toe osteonecrosis following trauma affects the distal weight-bearing structures essential for balance and push-off during ambulation. While involving smaller bones, this condition can significantly impact gait mechanics and may require specialized podiatric or orthopedic management.
Documentation Requirements
- ✓Specific identification of right toe(s) involvement
- ✓Documentation of previous trauma to right toe(s)
- ✓Clinical or radiological evidence of bone necrosis in toe bones
- ✓Number and specific toes affected when documented
- ✓Assessment of gait impact and balance issues
- ✓Current pain levels and functional limitations
- ✓Treatment history and response to interventions
- ✓Impact on weight-bearing and ambulation patterns
Commonly Confused Codes
- •M87.278 — Osteonecrosis due to previous trauma, left toe(s) (wrong laterality)
- •M87.279 — Osteonecrosis due to previous trauma, unspecified toe(s) (when laterality is documented)
- •M87.274 — Osteonecrosis due to previous trauma, right foot (broader anatomical involvement)
- •M87.377 — Other secondary osteonecrosis, right toe(s) (non-traumatic secondary cause)
- •S92.101A — Fracture of unspecified toe(s), right foot (acute fracture, not osteonecrosis)